+/*
+ * User-settable options (used with setsockopt).
+ */
+#define UDP_ENCAP 0x01
+
+
+/*
+ * UDP Encapsulation of IPsec Packets options.
+ */
+/* Encapsulation types. */
+#define UDP_ENCAP_ESPINUDP_NON_IKE 1 /* draft-ietf-ipsec-nat-t-ike-00/01 */
+#define UDP_ENCAP_ESPINUDP 2 /* draft-ietf-ipsec-udp-encaps-02+ */
+
+/* Default ESP in UDP encapsulation port. */
+#define UDP_ENCAP_ESPINUDP_PORT 500
+
+/* Maximum UDP fragment size for ESP over UDP. */
+#define UDP_ENCAP_ESPINUDP_MAXFRAGLEN 552
+